[lgessler]

> These two statements are at odds. If you can tell one you can tell the inverse.

Only if you treat candidate aptitude as binary. Really, aptitude is probably better thought of as a spectrum, and if that's the case then it is not a contradiction to say that you know that (1) someone wouldn't be an obviously bad employee and (2) that same candidate might only be a meh employee.

[MikeTaylor]

Exactly. You want to know, roughly, something like "is this candidate in the top 10%?". You might conclude "She seems to be at about the 85th percentile, give or take 10%", so she might be in the top 10% of might not. But you might conclude "He seems to be at about te 50th percentile, give or take 10%", in which case you're not interested. There is a fundamental asymmetry here.